The booming network data flow and users' demand for high-speed network application are leading the optical communication networks towards the way of ultra-wideband networks. Due to such advantages like those features of arbitrary working wavelength, wideband gain, distributed amplification and the capability of using common optical fiber as gain medium of the Raman optic fiber amplifier, it has been widely used in modern communication network.
Various optical amplifier manufacturers have conducted extensive researches on relative techniques of the Raman optical fiber amplifier. U.S. Pat. No. 7,031,049 disclosed a Loss Point detection method of the Raman optic fiber amplifier; U.S. Pat. No. 7,916,384 disclosed a method that can realize closed-loop control of the Raman optical fiber amplifier based on PID. U.S. Pat. No. 8,139,285 disclosed a Raman optical fiber amplifier and its controlling method, characterize by real-time gain control of Raman optical fiber amplifier. The above stated patents have basically shown the technical development trend of the Raman optical fiber amplifier, that is: from simple Raman output safe power protection and simple power control at early stage to research on real-time gain control at present. The existing technological development trend shows that the control on the Raman optical fiber amplifier focuses more on real-time control on gain. However, with the development of optical communication technique, the traditional static optical network has gradually progressed into dynamic optical network. On one hand, the dynamic optical network will introduce more surge of light, light fluctuation and photovoltaic conversion noise into optical fiber amplifier; on the other hand, frequent up and down wave becomes the theme of dynamic optical network. These demands of new dynamic features of the optical fiber amplifier will surely require the optical fiber amplifier to have quick dynamic response feature. As a type of optical amplifier, the Raman optical fiber amplifier also needs to meet this new technical requirement, that is, to realize quick control on the Raman optical fiber amplifier. There is no disclosure of relative technique in prior art.